Energy storage systems have become increasingly used to deliver power to utility grids either as part of standalone energy storage systems or as part of a renewable energy source (e.g. wind generation or solar generation systems) with an integrated energy storage system. Energy storage systems also can be used in other applications than utility grids, such as but not limited to telecommunications, electric vehicles, electronic devices, and other applications. Energy storage systems can include one or more battery banks or other energy storage devices.
When using energy storage devices such as batteries in the above applications and others, control systems for monitoring and enhancing battery capacity can be useful. Some systems are known to balance and monitor batteries with respect to their states of charge. The state of charge (SOC) of a battery, as used herein, is generally defined as the percentage of the full capacity of a battery that is still available for further discharge.
Specific factors relative to SOC are known to contribute to the overall capacity and life expectancy of batteries. For example, Lithium-based batteries can degrade at a faster rate when at or near top of charge (TOC). The potential for faster levels of battery degradation can also exist when batteries are consistently charged or discharged at faster rates.